Aerially Deposited lead

ADL Variance

Aerially Deposited Lead (ADL) refers to lead deposited on highway shoulders from past leaded fuel vehicle emissions. Although leaded fuel was prohibited in California since the 1980's, ADL may still be present in soils adjacent to highways in use prior to that time. Soil within Caltrans right of way containing California hazardous waste concentrations of lead can be reused under the authority of a variance issued by the Department of Toxic Substances Control (DTSC).

The variance allow stockpiling, transporting, and reuse of soils with hazardous waste concentrations of lead below maximum allowable levels on Caltrans right of way when specific conditions are met.

Variance Background Information

ADL Specifications

ADL Burial Location Data

The ADL variance requires tracking of material placed within Caltrans right of way under the authority of the variances. Contract specifications require surveying the ADL burial location before and after placement of soil. The survey data must be reported on Construction Form CEM 1901 which is submitted to the RE and emailed to ADL@dot.ca.gov. The form and associated instructions are found at: Forms Used For Contract Administration.